TW202040281A - Light source device for exposure, exposure device, and exposure method - Google Patents

Abstract

The present invention provides a light source device for exposure that is able to synthesize light from a plurality of LED elements having different peak wavelengths, and is compactly configured, an exposure device using the light source device, and an exposure method. This light source device for exposure is provided with: a first LED array (71) having a plurality of first LED elements (72) that emit light of a first peak wavelength; a second LED array (75) having a plurality of second LED elements (76) that emit light of a second peak wavelength different from the first peak wavelength; a photosynthetic element (80) that is provided with two dichroic films (81) for transmitting light in a specific wavelength band and reflecting light in the other wavelength bands, and synthesizes light from the first and second LED arrays (71, 75); and a fly-eye lens (65) on which the light synthesized by the photosynthetic element (80) is incident.

Description

Light source device for exposure, exposure device and exposure method

The present invention relates to a light source device, exposure device, and exposure method for exposure, and more specifically, to a light source device for exposure that uses light irradiated from an LED (Light Emitting Diode) element as the light source , Exposure device and exposure method.

In exposure devices used in lithography of flat panel displays, printed substrates, and semiconductor devices, mercury lamps were previously used as UV (Ultraviolet) light sources. However, in recent years, restrictions on the use of mercury have become stricter, and LEDs for UV light sources are being promoted.

Here, when the mercury lamp and the previous resist in the wavelength range are used directly, the single-wavelength LED element has a narrower wavelength band than the mercury lamp. Therefore, it is known to combine LED elements with multiple wavelengths of g-ray (436 nm), h-ray (405 nm), and i-ray (365 nm), which are equivalent to mercury lamps with strong output in high-pressure mercury lamps. It is a UV light source (for example, refer to Patent Documents 1 and 2).

Patent Document 1 describes a light source device that uses an X-shaped dichroic mirror to irradiate strong g-rays (436 nm), h-rays (405 nm), and i-rays equivalent to those in high-pressure mercury lamps. (365 nm) wavelength of light combining the UV light of a plurality of LED elements. In addition, Patent Document 2 describes an LED-type ultraviolet irradiator, which is provided with a plurality of LED light sources that emit UV light in the wavelength bands of 360 nm to 380 nm, 390 nm to 410 nm, and 420 nm to 450 nm, and for each Multiple dichroic mirrors equipped with LED light source. Furthermore, Patent Document 2 describes the use of UV LED light emitted at a wavelength of less than 300 nm, for example, a wavelength of 240 nm nominally. Prior art literature Patent literature

Patent Document 1: Japanese Patent Laid-Open No. 2018-10294 Patent Document 2: Japanese Patent Laid-Open No. 2010-263218

[The problem to be solved by the invention]

However, with regard to the set wavelength of the UV light source, when it is the wavelength that efficiently sensitizes the resist, the LED light source consumes less power and can reduce the cooling time caused by the heat of the light source, so it is better. Generally speaking, in the exposure apparatus, in order to reduce the number of parts, effectively use the space in the apparatus, and reduce the weight, there is a demand for miniaturization of the UV light source. Regarding the light from the LED array, although each LED element has a condenser lens, unless an optical member such as a convex lens is used separately, the light tends to be non-parallel and diffuse. Therefore, it is necessary to shorten the optical path length and miniaturize the light source device. Especially in the exposure device facing the display, a wider area must be exposed at one time, so the size of the light source also becomes larger, and the necessity of miniaturization is higher.

The light source device described in Patent Document 1 uses an X-shaped dichroic mirror to reduce the installation area, but there is still room for further miniaturization. In addition, the LED-type ultraviolet irradiator described in Patent Document 2 uses three or more dichroic mirrors in series, as a miniaturized LED light source, there is still room for improvement.

In addition, the inventors used the previous resists to conduct experiments, and as a result, found a resist with higher exposure sensitivity at a shorter wavelength than i-ray (365 nm). It is believed that the reason is that the polymerization initiator of the resist not only absorbs the absorption peak wavelength, but also absorbs the surrounding wavelengths, but if the absorption wavelength region extends to the visible light region, there will be problems caused by the use of the resist In this case, the absorption peak wavelength is deliberately set to be shorter than the g-ray, h-ray, and i-ray of the mercury lamp. As such use, for example, a resist for color filters of displays or image sensors can be cited. Therefore, a light source device that sensitizes such resists more efficiently is also expected.

The present invention was completed in view of the above problems, and its object is to provide a light source device for exposure that combines light from a plurality of LED elements with different peak wavelengths and is constructed in a compact size, an exposure device using the light source device, and exposure method. [Technical means to solve the problem]

The above object of the present invention is achieved by the following configuration. (1) A light source device for exposure, which includes: The first LED array has a plurality of first LED elements emitting light of the first peak wavelength; The second LED array has a plurality of second LED elements that emit light with a second peak wavelength different from the first peak wavelength; A light synthesis element that synthesizes the light of the first and second LED arrays; and A fly-eye lens for incident light synthesized by the above-mentioned light synthesis element; and The light synthesizing element includes two dichroic films that transmit light in a specific wavelength band and reflect light in other wavelength bands, and the two dichroic films are inclined with respect to the optical axis direction from the light synthesizing element to the fly-eye lens, And the close contact on the fly eye lens side is roughly V-shaped, The first LED array is arranged on the side opposite to the fly-eye lens with respect to the light combining element in the optical axis direction, The second LED array is arranged on the side of the light combining element so as to cross the optical axis direction. (2) The light source device for exposure as described in (1), wherein the peak wavelength of light irradiated from either the first LED element and the second LED element is 360-380 nm, The peak wavelength of the light irradiated from the other of the first LED element and the second LED element is 300-355 nm or 385-410 nm, The peak wavelengths of the first LED element and the second LED element are separated by 20 nm or more. (3) The light source device for exposure as described in (1) or (2), wherein the length of the second LED array arranged on the side of the light combining element is longer than that of the light combining element and opposite to the fly-eye lens. The length of the first LED array on the side is short. (4) The light source device for exposure according to any one of (1) to (3), wherein the light combining element is a two-piece dichroic mirror or a dichroic mirror. (5) The light source device for exposure as described in (1), wherein the light combining element is two dichroic mirrors each having the dichroic film, The end of each dichroic mirror is cut to be parallel to the optical axis direction. (6) The light source device for exposure as described in (5), further comprising two dichroic mirror fixing frames for fixing the dichroic mirrors respectively and opening at the sides where the two dichroic mirrors are in close contact with each other, The front end on the fly-eye lens side of the dichroic mirror fixing frame is cut to be perpendicular to the optical axis direction. (7) The light source device for exposure according to any one of (1) to (6), wherein the second LED array has two types of LEDs arranged alternately at 90° intervals on a plane orthogonal to the optical axis direction. 2 second LED arrays. (8) An exposure device including: an illumination device having the light source device for exposure as described in any one of (1) to (7); Workpiece support department, which supports the work piece; and The mask support part, which supports the mask; and The light irradiated from the lighting device is irradiated to the workpiece through the mask to transfer the pattern of the mask to the workpiece. (9) An exposure method that uses the exposure device described in (8) to irradiate the light irradiated from the illumination device to the workpiece through the mask to transfer the pattern of the mask to the workpiece. (10) A light source device for exposure, including: Corresponding to the photosensitive wavelength of the polymerization initiator of the photosensitive material provided on the substrate, a plurality of first LED elements emitting light of the first peak wavelength in the range of 360-380 nm; and emitting second LED elements in the range of 300-355 nm A plurality of second LED elements of light of peak wavelength; and The light of the first LED element and the light of the second LED element are mixed and emitted to the fly-eye lens. (11) The light source device for exposure according to (10), which includes an LED array in which the first LED element and the second LED element are arranged in a mixed manner. (12) The light source device for exposure as described in (9), which has: A first LED array having the above-mentioned plural first LED elements; A second LED array having the above-mentioned plurality of second LED elements; and A light synthesis element which synthesizes the light of the first and second LED arrays; and The light synthesizing element is arranged with a dichroic film that transmits light in a specific wavelength band and reflects light in other wavelength bands so as to be inclined with respect to the optical axis direction of the fly-eye lens from the light synthesizing element, Either the first LED array and the second LED array are arranged on the side opposite to the fly-eye lens with respect to the light combining element in the optical axis direction, The other of the said 1st LED array and the said 2nd LED array is arrange|positioned at the side of the said light combining element so that it may cross with the said optical axis direction. (13) An exposure device including: an illumination device having the light source device for exposure as described in any one of (10) to (12); Workpiece support department, which supports the work piece; and The mask support part, which supports the mask; and The light irradiated from the lighting device is irradiated to the workpiece through the mask to transfer the pattern of the mask to the workpiece. (14) An exposure method that uses the exposure device described in (13) to irradiate light irradiated from the illumination device to the workpiece through the mask to transfer a pattern of the mask to the workpiece. [Effects of Invention]

According to the light source device for exposure, the exposure device and the exposure method using the light source device of the present invention, a light source device capable of combining light from a plurality of LED elements with different peak wavelengths can be constructed in a compact structure, and can be utilized The synthetic light efficiently sensitizes the photosensitive material, thereby improving the efficiency of exposure work.

(First Embodiment) Hereinafter, the first embodiment of the exposure apparatus of the present invention will be described in detail based on the drawings. As shown in Fig. 1, the proximity exposure device PE uses a mask M smaller than the workpiece W as the material to be exposed, holds the mask M on the mask mounting table (mask support portion) 1, and holds the workpiece W on On the workpiece mounting table (work support portion) 2, in a state where the mask M and the workpiece W are close to each other and are arranged opposite to each other with a specific exposure gap, the light for pattern exposure is irradiated from the illumination device 3 to the mask M, thereby , Expose and transfer the pattern of the mask M to the workpiece W. In addition, the workpiece mounting table 2 is moved in steps in both the X-axis direction and the Y-axis direction relative to the mask M, and exposure and transfer are performed every step.

In order to move the workpiece stage 2 stepwise in the X-axis direction, an X-axis stage feed mechanism 5 for stepping the X-axis feed stage 5a in the X-axis direction is provided on the device base 4. In order to move the workpiece stage 2 in the Y-axis direction step by step, the X-axis feed stage 5a of the X-axis stage feed mechanism 5 is provided with a step-by-step movement of the Y-axis feed stage 6a in the Y-axis direction. Y-axis stage feeding mechanism 6. The Y-axis feeding table 6a of the Y-axis placing table feeding mechanism 6 is provided with a workpiece placing table 2. The workpiece W is held on the upper surface of the workpiece mounting table 2 in a state of being sucked by vacuum by a workpiece suction cup or the like. In addition, a substrate-side displacement sensor 15 for measuring the height of the lower surface of the mask M is arranged on the side of the workpiece mounting table 2. Therefore, the substrate-side displacement sensor 15 can move in the X and Y axis directions together with the workpiece mounting table 2.

A plurality of X-axis linear guide rails 51 (four in the embodiment shown) are arranged along the X-axis direction on the device base 4, and each rail 51 straddles the X-axis feeding table 5a. Slider 52 on the lower surface. Thereby, the X-axis feeding table 5a is driven by the first linear motor 20 of the X-axis stage feeding mechanism 5, and can reciprocate along the guide rail 51 in the X-axis direction. In addition, a plurality of Y-axis linear guide rails 53 are arranged on the X-axis feeding table 5a along the Y-axis direction, and a slider 54 fixed to the lower surface of the Y-axis feeding table 6a is straddled on each of the rails 53. Thereby, the Y-axis feeding table 6a is driven by the second linear motor 21 of the Y-axis stage feeding mechanism 6, and can reciprocate along the guide rail 53 in the Y-axis direction.

In order to move the workpiece placing table 2 in the vertical direction, between the Y-axis placing table feeding mechanism 6 and the workpiece placing table 2, there is provided: an up-and-down coarse motion device 7 whose positioning resolution is relatively low, but the movement stroke and movement The speed is higher; and the up and down micro-movement device 8, which can be positioned with high resolution compared with the up and down coarse-movement device 7, so that the workpiece mounting table can be moved up and down and the gap between the opposing surface of the mask M and the workpiece W is micro Adjust to a specific amount.

The vertical coarse movement device 7 moves the workpiece mounting table 2 up and down with respect to the fine movement mounting table 6b by an appropriate drive mechanism provided on the fine movement mounting table 6b described below. The stage coarse motion shaft 14 fixed to the bottom surface of the workpiece stage 2 is engaged with the linear motion bearing 14a fixed to the fine motion stage 6b, and is guided in the vertical direction with respect to the fine motion stage 6b. Furthermore, as for the vertical coarse movement device 7, it is preferable that although the resolution is low, the repeated positioning accuracy is high.

The vertical micro-motion device 8 is provided with a fixed table 9 fixed to the Y-axis feed table 6a, and a linear guide rail 10 installed on the fixed table 9 with its inner end side inclined obliquely downward, and is mounted on the rail 10 via a straddle The sliding body 12 of the sliding block 11 reciprocating along the guide rail 10 is connected to the nut (not shown) of the ball screw, and the upper end surface of the sliding body 12 is freely slidable in the horizontal direction and fixed to the micro-motion stage 6b The flanges 12a are connected.

In this way, if the screw of the ball screw is driven to rotate by the motor 17 installed on the fixed table 9, the nut, the slider 11 and the sliding body 12 move in an oblique direction along the guide rail 10, whereby the flange 12a moves up and down slightly . Furthermore, the vertical micro-motion device 8 can also be driven by a linear motor to drive the sliding body 12 instead of being driven by the motor 17 and a ball screw.

One of the upper and lower micro-movement devices 8 is installed on one end of the Z-axis feed table 6a in the Y-axis direction (the left end side of Fig. 1), and two of the vertical micro-movement devices 8 are installed on the other end side. 8 is independently driven and controlled. Thereby, the vertical micro-motion device 8 independently fine-adjusts the heights of the flanges 12a at three locations based on the measurement results of the gaps between the mask M and the workpiece W at multiple locations obtained by the gap sensor 27, thereby micro Adjust the height and inclination of the workpiece platform 2. Furthermore, when the height of the workpiece mounting table 2 can be sufficiently adjusted by the vertical micro-movement device 8, the vertical coarse-movement device 7 may be omitted.

In addition, the Y-axis feed table 6a is provided with a rod mirror 19 opposed to the Y-axis laser interferometer 18 for detecting the position of the workpiece mounting table 2 in the Y direction, and the X axis of the workpiece mounting table 2 The rod mirror (not shown) facing the X-axis laser interferometer at the position of the direction. The rod mirror 19 opposed to the Y-axis laser interferometer 18 is arranged along the X-axis direction on one side of the Y-axis feed table 6a, and the rod mirror 19 opposed to the X-axis laser interferometer moves on the Y axis. The other end side of the feeding table 6a is arranged along the Y-axis direction.

The Y-axis laser interferometer 18 and the X-axis laser interferometer are arranged so as to be opposed to the rod-shaped mirrors that each correspond to each other frequently, and are supported by the device base 4. Furthermore, two Y-axis laser interferometers 18 are installed at intervals in the X-axis direction. With two Y-axis laser interferometers 18, the Y-axis feed table 6a and even the workpiece mounting table 2 are detected in the Y-axis direction and the yaw error through the rod-type mirror 19. In addition, the X-axis laser interferometer detects the position of the X-axis feed table 5a and even the workpiece mounting table 2 in the X-axis direction through the opposing rod mirror.

The mask mounting table 1 includes: a mask base frame 24, which includes a substantially rectangular frame; and a mask frame 25, which is inserted through a gap at the central opening of the mask base frame 24 so as to be able to The way of moving in the Y and θ directions (in the X and Y planes) is supported; the mask base frame 24 is held at the starting position above the workpiece mounting table 2 by the support 4a protruding from the device base 4.

A frame-shaped mask holder 26 is provided on the lower surface of the central opening of the mask frame 25. That is, a plurality of mask holder suction grooves connected to a vacuum suction device not shown are provided on the lower surface of the mask frame 25, and the mask holder 26 is sucked and held by the mask through the plurality of mask holder suction grooves. Shield frame 25.

A plurality of mask suction grooves (not shown) are provided on the lower surface of the mask holder 26 for suctioning the peripheral part of the undrawn mask pattern of the mask M. The mask M passes through the mask suction groove and is The vacuum suction device shown in the figure is held on the lower surface of the mask holder 26 in a freely detachable manner.

As shown in FIG. 2, the illumination device 3 of the exposure device PE of this embodiment includes: a light source device 70 for irradiating ultraviolet rays, a plane mirror 66 for changing the direction of the light path EL emitted from the fly-eye lens 65 of the light source device 70, and The collimator 67 irradiates the light from the light source device 70 with parallel light, and the plane mirror 68 irradiates the parallel light toward the mask M.

In the lighting device 3, the light irradiated from the light source device 70 is incident on the incident surface of the fly-eye lens 65. The fly-eye lens 65 is used to make the illuminance distribution of the incident light on the irradiation surface as uniform as possible. In addition, the light emitted from the exit surface of the fly-eye lens 65 changes its traveling direction by the plane mirror 66, the collimator lens 67, and the plane mirror 68, and is converted into parallel light. In addition, the parallel light is irradiated as light for pattern exposure so as to be substantially perpendicular to the surface of the mask M held on the mask mounting table 1 and further to the workpiece W held on the workpiece mounting table 2 to expose the mask The pattern of M is exposed and transferred to the workpiece W.

Next, the light source device 70 will be described in detail with reference to FIG. 3. The light source device 70 of the present embodiment includes first and second LED arrays 71, 75 that irradiate light with different peak wavelengths, and a combination of light irradiated with different peak wavelengths from the first and second LED arrays 71, 75 The dichroic mirror 80 (80A, 80B) of the light combining element and the fly-eye lens 65 having a plurality of lens elements 65a arranged in a matrix.

In the first LED array 71, a plurality of first LED elements 72 are two-dimensionally aligned and arranged. The plurality of first LED elements 72 irradiate UV light having a peak wavelength (first peak wavelength) at any wavelength of 360 to 380 nm, for example. Furthermore, the peak wavelength of the first LED element 72 is preferably 360 to 370 nm, more preferably 365 nm.

In the second LED array 75, a plurality of second LED elements 76 are arranged two-dimensionally aligned. The plurality of second LED elements 76 are irradiated with UV light having a peak wavelength (second peak wavelength) at any wavelength of 300 to 355 nm or 385 to 410 nm, for example. Furthermore, the peak wavelength of the second LED element 76 is preferably 300-355 nm, more preferably 325-355 nm, and still more preferably 335 nm.

In addition, the first LED element 72 and the second LED element 76 are selected so that the peak wavelength of each light is separated by 20 nm or more. The reason why the peak wavelengths of the light of the first and second LED elements 72 and 76 are separated by more than 20 nm is that the dichroic mirror 80 must be separated by more than 20 nm in terms of its performance.

Furthermore, when the peak wavelength of the first LED element 72 is set to 365 nm, for example, the peak wavelength of the second LED element 76 may be set to 345 nm or less, or may be set to 385 nm or more.

The dichroic mirror 80 as a light-synthesizing element is an optical element: a thin film (dichroic film) 81 such as a multilayer film of a dielectric is formed on a plate-shaped transparent medium 82 such as glass or plastic, and has the ability to reflect light in a specific wavelength band and The characteristic of transmitting light in other wavelength bands. In the dichroic mirror 80, two dichroic mirrors 80A, 80B (two dichroic films 81) of approximately equal length L3 are arranged relative to the optical axis direction L of the fly-eye lens 65 from the dichroic mirror 80 (that is, along the optical path EL The direction) is inclined, and is arranged in a substantially V shape in a manner of close contact with the fly eye lens. Furthermore, in this embodiment, two dichroic mirrors 80A and 80B are combined at an angle of approximately 90°.

And, it is opposed to the opening side of the two dichroic mirrors 80A and 80B of the V-shape (the side opposite to the fly-eye lens 65 with respect to the dichroic mirror 80 in the optical axis direction L, and the left side in FIG. 3) In this way, the first LED array 71 is arranged. In addition, to cross the optical axis direction L (orthogonal in this embodiment), second LEDs are arranged on both sides of the two V-shaped dichroic mirrors 80A, 80B (up and down in FIG. 3). Array 75. Thereby, both the first LED array 71 and the second LED array 75 oppose the V-shaped dichroic mirror 80A or 80B at an angle of approximately 45°. Furthermore, in this embodiment, the term "second LED array 75 orthogonal to the optical axis direction L" includes not only the case where it is strictly orthogonal, but also includes the directivity of light from the second LED array 75 incident on the fly-eye lens 65 The degree of orthogonality allowed.

Furthermore, the number of the second LED elements 76 of the second LED array 75 is 1/2 of the number of the first LED elements 72 of the first LED array 71. That is, the length L2 of the second LED array 75 is approximately 1/2 of the length L1 of the first LED array 71, and is 1/2 of the length L3 of the dichroic mirror 80A or 80B. Thereby, all the light irradiated from the first LED array 71 passes through the dichroic mirror 80A or 80B, and all the light irradiated from the two second LED arrays 75 is reflected by the dichroic mirror 80A or 80B, and the light irradiated from the first LED array 71 It is combined with the light irradiated from the second LED array 75 and is incident on the incident surface of the fly-eye lens 65.

In this way, the two dichroic mirrors 80A, 80B are arranged in a substantially V shape in close contact with the fly eye lens 65 side, and the first LED array 71 is arranged in the optical axis direction L with respect to the V-shaped dichroic mirrors 80A, 80B. On the side opposite to the fly-eye lens 65, the second LED array 75 is divided and arranged on both sides of the V-shaped dichroic mirrors 80A and 80B so as to be orthogonal to the optical axis direction L, thereby shortening the first LED array 71 Up to the length of the fly-eye lens 65, the light source device 70 can be made compact. Furthermore, by arranging the first LED array 71 and the fly-eye lens 65 in close proximity, the optical efficiency is improved.

Furthermore, in FIG. 3, the first LED array 71 is set to a dominant wavelength having a peak wavelength at any wavelength of 360 to 380 nm, and the second LED array 75 is set to, for example, 300 to 355 nm or 385 to 410 nm. Any wavelength of the sub-wavelength with the peak wavelength. However, this embodiment is not limited to this, and the first LED array 71 may be set to, for example, a sub-wavelength having a peak wavelength at any wavelength of 300 to 355 nm or 385 to 410 nm, and the second LED array 75 may be set to It is the dominant wavelength with a peak wavelength at any wavelength from 360 to 380 nm.

Moreover, since the reflected light obtained by the dichroic mirrors 80A and 80B has higher optical efficiency than the transmitted light, it can be appropriately selected according to the sensitivity of the resist used. In addition, the lengths of the first LED array 71, the second LED array 75, and the dichroic mirrors 80A and 80B can also be changed according to specifications.

While the second LED array 75 passes through the interface of the dichroic mirror 80 once during reflection, the first LED array 71 passes through the interface of the dichroic mirror 80 twice. In addition, the light of the second LED array 75 is reflected by the dichroic mirror 80. Since the film thickness of the dichroic mirror 80 is proportional to the reflection wavelength, when the wavelength of the reflected light is shorter, the film thickness can be made thinner , And manufacturing becomes easy. Therefore, when the dichroic mirror 80 is used, it is preferable to use a relatively long peak wavelength for the first LED array 71 and a relatively short peak wavelength for the second LED array 75.

Specifically, as a preferable combination of the peak wavelength of the first LED array 71 and the peak wavelength of the second LED array 75, the following two combinations (A) and (B) can be cited. (A) Peak wavelength of the first LED array 71: 360～380 nm Peak wavelength of the second LED array 75: 300～355 nm (B) Peak wavelength of the first LED array 71: 385～410 nm Peak wavelength of the second LED array 75: 360～380 nm

In addition, generally speaking, the exposure sensitivity when using LED elements with various peak wavelengths to expose a color photoresist whose absorption peak wavelength region corresponds to i-rays (365 nm) is confirmed by experiments, and the results are as shown in Table 1. Show that the sensitivity is poor. Furthermore, Table 1 is based on 365 nm.

[Table 1] Wavelength [nm] 330 340 365 380 386 Exposure sensitivity ratio 3.1 2.5 1 0.6 0.25

According to Table 1, for example, the exposure sensitivity of light with a wavelength of 330 nm is 3 times that of light with a wavelength of 365 nm. Therefore, even if the output of the 365 nm LED element is about 30%, the same performance can be obtained. Therefore, by combining two kinds of LED elements according to the absorption peak wavelength region of the resist, the exposure time can be shortened, and thus the efficiency of the exposure step can be improved.

As an example, when the second LED element 76 is set to the dominant wavelength of 365 nm, and the first LED element 72 is set to the sub-wavelength of 385 nm, the long-wavelength region (385 nm) LED element and the 365 nm LED element Compared with, although the exposure sensitivity is low, the output is high, and the transmittance is high when the wavelength is longer. Specifically, as shown in Fig. 4, the transmittance of the 385 nm LED element arranged in the first LED array 71 is about 98%. As shown in Fig. 5, the reflection of the 365 nm LED element arranged in the second LED array 75 The rate is about 100%, and the overall loss is about 2%. Furthermore, FIG. 4 is a graph showing the transmittance of the dichroic mirror 80 as an example, and FIG. 5 is a graph showing the reflectance of the dichroic mirror 80 in FIG. 4. The light emitted from each LED element 72, 76 is incident on the dichroic mirror through the condenser lens at an angle θ1, θ2 (refer to Fig. 3) of 42°～48° relative to the surface of the dichroic mirror 80A, 80B. 80A, 80B, each graph shows the transmittance and reflectance when θ1, θ2=42°, 45°, 48°.

In this way, by combining the above two types of LED elements, the exposure time can be shortened. Furthermore, as a combination of two types of LED elements, one with a peak wavelength of 365 nm and 330 nm can also be used, which can shorten the exposure time with the same output.

Furthermore, by combining the LED element that becomes the dominant wavelength and the LED element having a wavelength longer than the dominant wavelength, the formed pattern can be stabilized. For example, when only a single-wavelength LED element with a peak wavelength of 365 nm is used for exposure, the pattern formed by the resist is weakly hardened, and the pattern is easily peeled off during the development step. Peeling easily occurs at the end of the pattern, which originates from the light leakage of the pattern passing through the mask and the polymerization initiator of the resist. Generally, in order to suppress peeling, it is necessary to increase the exposure time or adjust the steps before and after. By using the combination as in this example, the output is higher, and the transmittance of the resist is higher corresponding to the longer wavelength, and the light easily reaches the deep part of the resist The LED element with a wavelength of 385 nm can stabilize the pattern.

(Second Embodiment) Next, the light source device 70 of the second embodiment will be described with reference to FIG. 6. As shown in FIG. 6, in the light source device 70 of the present embodiment, the two dichroic mirrors 80A, 80B have both ends 83 cut so as to be parallel to the optical axis direction L from the dichroic mirror 80 to the fly-eye lens 65. Thereby, the dichroic films 81 of the two dichroic mirrors 80A and 80B are connected to each other at the top of the V shape. Therefore, the dichroic mirrors 80A and 80B can make the light irradiated from the first LED array 71 cover the width of the dichroic mirror 80 The direction (the direction orthogonal to the optical axis direction L) is uniformly transmitted across the entire area, and the light irradiated from the second LED array 75 can be reflected in a wider range, thereby improving efficiency. Furthermore, in this case, the first LED array 71 and the second LED array 75 can also be arranged by swapping the positions relative to the two dichroic mirrors 80A and 80B. The other structures and functions are the same as those of the first embodiment of the present invention.

(Third Embodiment) Next, the light source device 70 of the third embodiment will be described with reference to FIG. 7. As shown in FIG. 7, this embodiment uses two dichroic mirror fixing frames 85 to describe the method of fixing the two dichroic mirrors 80A and 80B described in the above embodiment.

The dichroic mirror fixing frame 85 has the following shape: three frames 85a, 85b, 85c covering three of the four sides of the rectangular dichroic mirrors 80A, 80B are combined into a substantially U-shape, and the dichroic mirrors 80A, 80B The sides facing each other are open. In addition, one side of the dichroic mirrors 80A and 80B is fitted into the groove 86 of the frame 85a of the substantially U-shaped dichroic mirror fixing frame 85. The upper surfaces of the dichroic mirrors 80A and 80B are interposed by the buffer material 88 by The pressing screw 87 provided on the frame 85c is pressed against the frame 85b to be fixed to the dichroic mirror fixing frame 85.

In addition, in FIG. 7, corresponding to the second embodiment, two dichroic mirrors 80A and 80B butted in a V-shaped front end 83, and a dichroic mirror fixing frame 85 for fixing the dichroic mirrors 80A and 80B, respectively (Frames 85b, 85c) The front end 85d is cut to be parallel to the optical axis direction L from the dichroic mirror 80 to the fly-eye lens 65, and is closely attached with no gap, preferably without gap.

Furthermore, the front end 85d of the fly-eye lens side of the dichroic lens fixing frame 85 (frames 85b, 85c) combined in a V shape is cut to be perpendicular to the optical axis direction L of the fly-eye lens 65 from the dichroic mirror 80 to form a mutual It is the plane of the same plane. Thereby, the length of the dichroic mirror fixing frame 85 can be cut to make the two dichroic mirrors 80A and 80B closer to the fly-eye lens 65, thereby improving efficiency and miniaturizing the light source device 70. Furthermore, in Fig. 7(b) of the dichroic mirror fixing frame 85 (frame body 85a, 85b, 85c) supporting the dichroic mirrors 80A and 80B, the range outside the arrow is arranged on the outside of the optical path of the exposure light. The color mirror fixing frame 85 will not become an obstacle to exposure.

As a variation of this embodiment, as shown in Fig. 8, in the dichroic mirror fixing frame 85, three frames 85a, 85b, 85c are respectively formed with grooves 86, and the sides of the dichroic mirrors 80A, 80B ( The three sides) can also be fitted into the three grooves 86 and fixed with an adhesive. Also, as shown in FIG. 7, the front end 83 of the two dichroic mirrors 80A, 80B and the front end 85d of the two dichroic mirror fixing frame 85 are in close contact with each other without gaps, preferably without gaps. then.

(Fourth Embodiment) Next, the light source device 70 of the fourth embodiment will be described with reference to FIG. 9. As shown in FIG. 9, in this embodiment, on the sides of the two V-shaped dichroic mirrors 80A and 80B, two types of two second LED arrays 75A, 75A and 80B are arranged on a plane perpendicular to the optical axis direction L. 75B. In addition, the two second LED arrays 75A and 75A and the other two second LED arrays 75B and 75B are alternately arranged on the plane at 90° intervals.

For example, the first LED array 71 uses LED elements 72 with a peak wavelength of 365 nm, a second LED array 75A uses LED elements 76A with a peak wavelength of 385 nm, and the other second LED array 75B uses LED elements 76B with a peak wavelength of 330 nm. In addition, in the case of using the first LED array 71 and a second LED array 75A, and the case of using the first LED array 71 and the other second LED array 75B, two different dichroic mirrors 80 and 90 are switched. Therefore, the dichroic mirrors 80 and 90 are arranged in a mirror mounting portion (not shown) so that the mounting state can be changed and detached. In addition, the dichroic mirror 90 is the same as the dichroic mirror 80 described in Embodiments 1 to 3, and is composed of two dichroic mirrors 90A and 90B. However, in this embodiment, the dichroic mirrors 80 and 90 correspond to the two second LED elements 76A and 76B, and their reflection characteristics of a specific wavelength band are different.

When switching between the second LED arrays 75A and 75B, the dichroic mirror 80 when the first LED array 71 and the second LED array 75A are used and the dichroic mirror 90 when the first LED array 71 and the other second LED array 75B are used are used for color separation The arrangement directions of the mirrors 80A, 80B, 90A, and 90B are arranged to be orthogonal to each other on the plane.

With this, when the light source device is set to a form that can switch between the two second LED elements 76A and 76B for exposure, only the dichroic mirrors 80 and 90 need to be exchanged, the second LED arrays 75A and 75B do not need to be exchanged, and there is no need to exchange the second LED array 75A. 、Replacement of electrical system or cooling system in 75B situation.

In addition, as a variation of the present embodiment, when the peak wavelengths of the two second LED arrays 75A and 75B are the same, it may be configured to be able to rotate the dichroic mirror 80. In addition, when the LED arrays 75A and 75B are used, respectively, the direction of the dichroic mirror 80 is rotated according to the LED arrays 75A and 75B used.

In addition, the present invention is not limited to the above-mentioned respective embodiments, and changes, improvements, etc. can be appropriately made. For example, although the above-mentioned embodiment has described the method of synthesizing light of different peak wavelengths by a dichroic mirror, the light synthesizing element of the present invention is not limited to this, and may be a dichroic beam.

As shown in Figure 10, the color separation ring 180 is a combination of three right-angled rings 181, 182, 183 of materials with higher transmittance such as glass or plastic. When viewed from the side, each of the scallops 181, 182, and 183 has a substantially right-angled isosceles triangle shape. The color separation ring 180 has a side-view rectangular shape formed by combining the sides other than the hypotenuse of the color separation 181 with the oblique sides of the color separation 182 and 183 through a color separation film not shown. In addition, the interface 184 of the dichroic film 181, 182 and the interface 185 of the dichroic film 181, 183 are inclined at an angle of approximately 45° with respect to the optical axis direction L, and the two interfaces 184, 185 cross at 90° The way to form. As a result, the two dichroic films are arranged in a substantially V-shape so as to be in close contact with the fly eye lens.

The color separation ring 180 can make the light from the first LED array 71 and the second LED array 75 pass through the interfaces 181a, 182a, 182b, 183a, 183b, 184, and 185 (including the light-incident surface and the light-emitting surface) the same number of times. Moreover, by using the color separation lens 180, there is no need for a structure for closely connecting two dichroic mirrors.

In addition, in the above-mentioned embodiment, dichroic mirrors arranged in a V shape are used, and the light emitted from the two LED arrays is emitted to the fly-eye lens 65 through the dichroic mirrors. On the other hand, as another optical device 70A of the present invention, as shown in FIG. 11, it does not have dichroic mirrors 80A and 80B, and is composed of only one LED array 78. The LED array 78 can also directly oppose the fly-eye lens 65 To configuration.

In this case, in the LED array 78, the first LED element 72 and the second LED element 76 are aligned and arranged in a mixed manner. Therefore, regarding the light irradiated from the LED array 78, the light of the first LED element 72 and the light of the second LED element 76 are mixed and emitted to the fly-eye lens 65.

Regarding the peak wavelength of the light irradiated from the second LED element 76, the sensitivity is matched with the peak wavelength (photosensitive wavelength) of the polymerization initiator of the photosensitive material to be any wavelength of 300-355 nm. Regarding the peak wavelength of the light irradiated from the first LED element 72 The peak wavelength of light makes the sensitivity consistent with the absorption base of the polymerization initiator and becomes any wavelength in the range of 360-380 nm. Specifically, the peak wavelength of the light irradiated from the second LED element 76 is set to, for example, 335 nm, and the peak wavelength of the light irradiated from the first LED element 72 is set to, for example, 365 nm.

Thereby, the resist can be efficiently sensitized, and no light synthesis element such as a dichroic mirror for synthesizing light is required. Furthermore, the LED array 78 and the fly-eye lens 65 can be arranged close to each other, thereby improving efficiency. Moreover, there is no need to limit the wavelength interval of the light of the first and second LED elements 72, 76 to 20 nm or more, and the peak wavelength can be freely set according to the sensitivity of the photosensitive material.

In addition, as shown in another modification of FIG. 12, the light source device 70B may be constituted by one dichroic mirror 80 instead of the two dichroic mirrors 80A and 80B arranged in a V shape. In this case, the first LED array 71 having a plurality of first LED elements 72 and the second LED array 75 having a plurality of second LED elements 76 are arranged orthogonally, and the dichroic mirror 80 is opposed to the first LED array 71 and the second LED array The 75 is configured with an incline of 45°.

Thereby, the light irradiated from the first LED array 71 passes through the dichroic mirror 80 and enters the fly-eye lens 65, the light irradiated from the second LED array 75 is reflected by the dichroic mirror 80, is combined with the light irradiated from the first LED array 71 and enters the compound eye Lens 65.

Furthermore, the color filter resist is made by mixing a polymerization initiator, a pigment, a polymerizable monomer, a polymer, and a solvent. As a polymerization initiator having an absorption peak in the range of 300 to 355 nm, it can List the following (1) to (10). Among these polymerization initiators, high-sensitivity (9) Irgacure OXE01 and (10) Irgacure OXE02 are preferred.

(1) Name: Omnirad184 (registered trademark), (1-hydroxycyclohexyl-phenyl ketone) manufactured by IGM Resins BV [Chemical 1]

(2) Name: Omnirad1173 (registered trademark), (2-hydroxy-2-methyl-1-phenylacetone) manufactured by IGM Resins BV [Chemical 2]

(3) Name: Omnirad651 (registered trademark), (2,2-dimethoxy-2-phenylacetophenone) manufactured by IGM Resins BV [Chemical 3]

(4) Name: Omnirad 2959 (registered trademark), (1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-methylacetone) manufactured by IGM Resins BV [Chem 4]

(5) Name: Omnirad127 (registered trademark), (2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropanyl)benzyl)phenyl) manufactured by IGM Resins BV 2-Methylpropan-1-one) [Chemical 5]

(6) Name: Omnirad369 (registered trademark), (2-benzyl-2-(dimethylamino)-4'-(N-morpholinyl)butyrobenzene) manufactured by IGM Resins BV (Chemical Formula 6)

(7) Name: Omnirad379EG (registered trademark), (2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-benzene) manufactured by IGM Resins BV Base) butan-1-one) [化7]

(8) Name: Omnirad MBF (registered trademark), (methyl benzoate) manufactured by IGM Resins BV [Chemical 8]

(9) Name: Irgacure OXE01 (registered trademark), (1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(o-benzoyl) manufactured by BASF Japan Co., Ltd. Oxime) [Chemical 9]

(10) Name: Irgacure OXE02 (registered trademark), (ethyl ketone, 1-[9-ethyl-6-(2-methylbenzyl)-9H-carbazole-3 manufactured by BASF Japan Co., Ltd.) -Based]-, 1-(O-acetoxime) [Chemical 10]

In addition, this application is based on a Japanese patent application (Japanese Patent Application No. 2019-038939) filed on March 4, 2019, and the content is incorporated into this application as a reference.

1: Mask stage 2: Workpiece mounting table 3: Lighting device 4: Device base 4a: Pillar 5: X-axis table feed mechanism 5a: X axis feed table 6: Y-axis table feed mechanism 6a: Y axis feed table 6b: Micro-motion stage 7: Up and down coarse moving device 8: Up and down micro movement device 9: Fixed table 10: Rail 11: Slider 12: Slippery body 12a: flange 14: Coarse moving axis of the stage 14a: Linear motion bearing 15: substrate side displacement sensor 17: Motor 18: Y-axis laser interferometer 19: Rod mirror 20: 1st linear motor 21: 2nd linear motor 24: Mask base frame 25: Mask frame 26: Mask holder 27: Gap sensor 51: Rail 52: Slider 53: Rail 54: Slider 65: compound eye lens 65a: lens element 66: flat mirror 67: collimator lens 68: flat mirror 70: Light source device 70A: Light source device 70B: Light source device 71: 1st LED array 72: The first LED element 75: 2nd LED array 75A: 2nd LED array 75B: 2nd LED array 76: 2nd LED element 76A: 2nd LED element 76B: 2nd LED element 78: LED array (light source device) 80: Light synthesis element (dichroic mirror) 80A: Light synthesis element (dichroic mirror) 80B: Light synthesis element (dichroic mirror) 81: Dichroic film 82: transparent medium 83: end 85: dichroic mirror fixed frame 85a: frame 85b: frame 85c: frame 85d: The front end of the dichroic mirror fixed frame 86: Slot 87: Press the screw 88: buffer material 90: dichroic mirror 90A: Dichroic mirror 90B: Dichroic mirror 180: Light synthesis element (color separation 鏡) 181: right angle 182: right angle 183: right angle 181a: Interface 182a: Interface 182b: Interface 183a: Interface 183b: Interface 184: Interface 185: Interface EL: light path L: Optical axis direction L1: Length of the first LED array L2: Length of the second LED array L3: Length of dichroic mirror M: Mask PE: Proximity Exposure Device W: Workpiece (substrate) θ1: Angle θ2: Angle

Fig. 1 is a front view of the exposure apparatus according to the first embodiment of the present invention. Fig. 2 is a diagram showing the structure of the lighting device shown in Fig. 1. Fig. 3 is a schematic configuration diagram of the light source device of the first embodiment. Fig. 4(a) is a graph showing the transmittance of a dichroic mirror as an example, and Fig. 4(b) is an enlarged view of part IV of Fig. 4(a). Fig. 5(a) is a graph showing the reflectance of the dichroic mirror of Fig. 4, and Fig. 5(b) is an enlarged view of part V of Fig. 5(a). Fig. 6 is a schematic configuration diagram of a light source device of the second embodiment. Fig. 7(a) is a side view showing the installation state of the dichroic mirror in the light source device of the third embodiment, and Fig. 7(b) is a view viewed from the direction A in Fig. 7(a). Fig. 8(a) is a side view showing another mounted state of the dichroic mirror in the light source device of the modified example of the third embodiment, and Fig. 8(b) is a view of Fig. 8(a) viewed from the direction B. 9 is a schematic plan view showing two types of second LED arrays and two dichroic mirrors arranged on a plane perpendicular to the optical axis direction in the case of the light source device of the fourth embodiment. Fig. 10 is a schematic configuration diagram of a light source device according to a modification of the present invention using a color separation ring. Fig. 11 is a front view of an LED array of a light source device as another modification of the present invention. Fig. 12 is a front view of an LED array of a light source device as yet another modification of the present invention.

65: compound eye lens

65a: lens element

70: Light source device

71: 1st LED array

72: The first LED element

75: 2nd LED array

76: 2nd LED element

80: Light synthesis element (dichroic mirror)

80A: Light synthesis element (dichroic mirror)

80B: Light synthesis element (dichroic mirror)

81: Dichroic film

82: transparent medium

L: Optical axis direction

L1: Length of the first LED array

L2: Length of the second LED array

L3: Length of dichroic mirror

θ1: Angle

θ2: Angle

Claims (14)

A light source device for exposure, which has: The first LED array has a plurality of first LED elements emitting light of the first peak wavelength; The second LED array has a plurality of second LED elements that emit light with a second peak wavelength different from the first peak wavelength; A light synthesis element that synthesizes the light of the first and second LED arrays; and A fly-eye lens for incident light synthesized by the above-mentioned light synthesis element; and The light synthesizing element includes two dichroic films that transmit light in a specific wavelength band and reflect light in other wavelength bands, and the two dichroic films are inclined with respect to the optical axis direction from the light synthesizing element to the fly-eye lens, And the close contact on the fly eye lens side is roughly V-shaped, The first LED array is arranged on the side opposite to the fly-eye lens with respect to the light combining element in the optical axis direction, The second LED array is arranged on the side of the light combining element so as to cross the optical axis direction. The light source device for exposure according to claim 1, wherein the peak wavelength of the light irradiated from any one of the first LED element and the second LED element is 360-380 nm, The peak wavelength of the light irradiated from the other of the first LED element and the second LED element is 300-355 nm or 385-410 nm, The peak wavelengths of the first LED element and the second LED element are separated by 20 nm or more. The light source device for exposure according to claim 1 or 2, wherein the length of the second LED array arranged on the side of the light combining element is longer than that of the first LED array arranged on the side opposite to the fly-eye lens with respect to the light combining element The length is short. The light source device for exposure according to any one of claims 1 to 3, wherein the light combining element is a two-piece dichroic mirror or a dichroic mirror. Such as the light source device for exposure of claim 1, wherein the light combining element is two dichroic mirrors each having the dichroic film, The end of each dichroic mirror is cut to be parallel to the optical axis direction. For example, the light source device for exposure according to claim 5, which is further provided with two dichroic mirror fixing frames that respectively fix the dichroic mirrors and open on the side where the two dichroic mirrors are in close contact, The front end on the fly-eye lens side of the dichroic mirror fixing frame is cut to be perpendicular to the optical axis direction. The light source device for exposure according to any one of claims 1 to 6, wherein the second LED array has two second LED arrays of two types alternately arranged at 90° intervals on a plane orthogonal to the optical axis direction. An exposure device comprising: an illumination device having a light source device for exposure according to any one of claims 1 to 7; Workpiece support department, which supports the work piece; and The mask support part, which supports the mask; and The light irradiated from the lighting device is irradiated to the workpiece through the mask to transfer the pattern of the mask to the workpiece. An exposure method that uses the exposure device of claim 8 to irradiate the light irradiated from the illumination device to the workpiece through the mask to transfer the pattern of the mask to the workpiece. A light source device for exposure, which has: Corresponding to the photosensitive wavelength of the polymerization initiator of the photosensitive material provided on the substrate, a plurality of first LED elements emitting light of the first peak wavelength in the range of 360-380 nm; and emitting second LED elements in the range of 300-355 nm A plurality of second LED elements of light of peak wavelength; The light of the first LED element and the light of the second LED element are mixed and emitted to the fly-eye lens. According to claim 10, the light source device for exposure includes an LED array in which the first LED element and the second LED element are arranged in a mixed manner. For example, the light source device for exposure of claim 10, which has: A first LED array having the above-mentioned plural first LED elements; A second LED array having the above-mentioned plurality of second LED elements; and A light synthesis element which synthesizes the light of the first and second LED arrays; and The light synthesizing element is arranged with a dichroic film that transmits light in a specific wavelength band and reflects light in other wavelength bands so as to be inclined with respect to the optical axis direction of the fly-eye lens from the light synthesizing element, Either the first LED array and the second LED array are arranged on the side opposite to the fly-eye lens with respect to the light combining element in the optical axis direction, The other of the said 1st LED array and the said 2nd LED array is arrange|positioned at the side of the said light combining element so that it may cross with the said optical axis direction. An exposure device comprising: an illumination device having a light source device for exposure as in any one of Claims 10 to 12; Workpiece support department, which supports the work piece; and The mask support part, which supports the mask; and The light irradiated from the lighting device is irradiated to the workpiece through the mask to transfer the pattern of the mask to the workpiece. An exposure method that uses the exposure device of claim 13 to irradiate light irradiated from the illumination device to the workpiece through the mask to transfer the pattern of the mask to the workpiece.

Images